From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: <2ef52570c9c6f8a5f541e1ab9465159e@brasstown.quanstro.net> References: <2ef52570c9c6f8a5f541e1ab9465159e@brasstown.quanstro.net> Date: Mon, 3 Jun 2013 11:21:20 -0700 Message-ID: From: Steven Stallion To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: multipart/alternative; boundary=047d7b6d7d8a04919404de440897 Subject: Re: [9fans] ARM and u-boot Topicbox-Message-UUID: 627a04de-ead8-11e9-9d60-3106f5b1d025 --047d7b6d7d8a04919404de440897 Content-Type: text/plain; charset=ISO-8859-1 On Mon, Jun 3, 2013 at 6:19 AM, erik quanstrom wrote: > unfortunately, as far as i know plan 9 can't be used as a primary > loader most of the environments where uboot is used because > we haven't written the (usually small) memory initialization code, etc. > It's more than that. Many board vendors will use a secured stage 1 bootloader that assumes U-Boot. It's probably possible to shove in a different second stage loader, but you'll still need to do board initialization as you mentioned. It's not that onerous and there is source out there, but I think it's really a question of motivation. U-Boot is supported by the same vendors and covers of the behavior you will likely want in a boot loader (and then some). Board configs are easy to customize so that you aren't carrying around a massive binary. The binary I use for the Arndale is measured in kilobytes, not megabytes. Every SoC is going to have a different process - in the end, you'll have something that will probably look quite a bit like U-Boot without any real benefit. I'd rather tilt at other windmills... --047d7b6d7d8a04919404de440897 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
On Mon, Jun 3, 2013 at 6:19 AM, erik quanstrom <qua= nstro@quanstro.net> wrote:
unfortunately, as far as i know plan 9 can&#= 39;t be used as a primary
loader most of the environments where uboot is used because
we haven't written the (usually small) memory initialization code, etc.=

It's more than that. Many bo= ard vendors will use a secured stage 1 bootloader that assumes U-Boot. It&#= 39;s probably possible to shove in a different second stage loader, but you= 'll still need to do board initialization as you mentioned. It's no= t that onerous and there is source out there, but I think it's really a= question of motivation. U-Boot is supported by the same vendors and covers= of the behavior you will likely want in a boot loader (and then some). Boa= rd configs are easy to customize so that you aren't carrying around a m= assive binary. The binary I use for the Arndale is measured in kilobytes, n= ot megabytes.

Every SoC is going to have a different proc= ess - in the end, you'll have something that will probably look quite a= bit like U-Boot without any real benefit. I'd rather tilt at other win= dmills...=A0
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